Discrete Adjoint Optimization for Improved Aerodynamics Using the Spalart-Allmaras Model

• Published in: International Review on Modeling and Simulations Vol. 18; no. 2; p. 83
• Main Authors: Ntantis, Efstratios, Xezonakis, Vasileios
• Format: Journal Article
• Language: English
• Published: Naples Praise Worthy Prize 30.04.2025
• Subjects: Aerodynamics; Airfoils; Design parameters; Drag coefficients; Low speed; Optimization techniques; Parameter sensitivity; Reynolds number; Shape optimization; Spalart-Allmaras turbulence model; Turbulence models
• ISSN: 1974-9821; 2533-1701; 1974-9821
• DOI: 10.15866/iremos.v18i2.25961

The adjoint approach is a powerful methodology for high-precision aerodynamic shape optimization, enabling the rapid computation of derivatives of objective functions with respect to design variables. This study explores the discrete adjoint method. It offers a theoretical analysis of its use as an alternative technique for calculating objective functions and design parameters' sensitivities, focusing on a multipoint NACA0012 airfoil. This paper includes a qualitative assessment of a test case with Mach and Reynolds numbers of 0.0294 and 0.667 million, respectively, and utilizes the Spalart-Allmaras turbulence model to enhance computational efficiency. The results demonstrate the effectiveness of the DAFoam tool, achieving a notably low drag coefficient and confirming its ability to generate optimal aerodynamic designs. Although the study does not address the post-processing of sensitivity data, it identifies potential directions for future research. This paper lays the groundwork for optimizing the NACA0012 airfoil in the low-speed (subsonic) regime and positions the discrete adjoint approach as a valuable tool for broad aerodynamic applications. Additionally, it is an educational resource for graduate students and engineers, contributing to the ongoing advancement of aerodynamic optimization techniques.